phi-pH diagram of V-Ti-H2O system during pressure acid leaching of converter slag containing vanadium and titanium

作者：Mu Wang zhong; Zhang Ting an^*; Dou Zhi he; Lu Guo zhi; Liu Yan

来源：Transactions of Nonferrous Metals Society of China, 2011, 21(9): 2078-2086.

DOI：10.1016/S1003-6326(11)60976-X

• phi-pH diagram
• V-Ti-H2O system
• pressure acid leaching
• converter slag
• vanadium
• titanium

To analyze the thermodynamic characteristics of leaching process of converter slag,phi-pH diagram of V-Ti-H2O system at oxygen partial pressure of 0.5 MPa, ionic mass concentration of 0.1 mol/kg and temperatures ranging from 60 to 200 degrees C was obtained by recently published critically assessed standard Gibbs energies and activity coefficients of various species. When pH<2, stable regions of V3+, VO2+ and VO2+ exist in the stable region of TiO2. The pH values of stable regions of vanadium and titanium decrease and redox potentials become more positive with the temperature increasing. Vanadium and titanium could be separated by one-step leaching based on thermodynamics. The experiment results of pressure acid leaching of converter slag show that leaching rates of vanadium and titanium are 96.87% and 8.76% respectively, at 140 degrees C of temperature, 0.5 MPa of oxygen partial pressure, 0.055-0.075mm of particle size, 15:1 of liquid to solid ratio, 120 min of leaching time, 500 r/min of stirring speed and 200 g/L of initial acid concentration. Vanadium and titanium could be selectively separated in the pressure acid leaching process, and the experiment result is in agreement with thermodynamic calculation result.

• 出版日期2011-9
• 单位东北大学